From:
Operating system: CentOS 5.4
PHP version: 5.3.2
Package: *General Issues
Bug Type: Bug
Bug description:Fatal Error "Call to a member function * on a non-object"
occurring randomly
Description:
------------
We have several servers running PHP 5.3.2 on CentOS 5.4 and a few on PHP
5.2.9
on FreeBSD. Reviewing our error logs, I have noticed a pattern of fatal
errors:
"Call to a member function * on a non-object". This occurs usually daily,
and
sometimes several times a day. When it occurs, it occurs on a single
server,
several times over a 2-3 minute span, and across different PHP sessions and
occurs in different functions in different classes. This issue does not
seem to
coincide with high traffic or with time of day. This issue has occurred on
each
of the webservers running CentOS, although I have noticed it occurring over
several releases of PHP. There are no other fatal PHP errors that occur
concurrently, nor are there any other external processes that are occurring
concurrently.
The only thing I can suspect is PHP garbage collection improperly deleting
objects, although debug_zval_dump() shows the object correctly constructed
and
never destructed prior to calling a member function.
After seeing this error occur on several functions in various classes, I
picked
one and added code to check is_object() and email me the results of
debug_zval_dump() when false. Although is_object() returns false, the dump
of
the object shows the following:
if (!is_object($this->flow_info))
{
debug_zval_dump($this);
}
output:
object(SEFlow)#13 (10) refcount(5){
...
["flow_info"]=>
object(FlowInfo)#14 (4) refcount(1){
...
Calling a function:
$this->flow_info->getElementsUnderBranch(__MAIN_BRANCH, false);
results in the fatal error:
Call to a member function getElementsUnderBranch() on a non-object in
/var/www/Qualtrics/Qualtrics/SurveyEngine/Flow/Flow.php on line 186
--
Edit bug report at http://bugs.php.net/bug.php?id=52083&edit=1
--
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=52083&r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=52083&r=trysnapshot53
Try a snapshot (trunk):
http://bugs.php.net/fix.php?id=52083&r=trysnapshottrunk
Fixed in SVN:
http://bugs.php.net/fix.php?id=52083&r=fixed
Fixed in SVN and need be documented:
http://bugs.php.net/fix.php?id=52083&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=52083&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=52083&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=52083&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=52083&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=52083&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=52083&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=52083&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=52083&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=52083&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=52083&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=52083&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=52083&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=52083&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=52083&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=52083&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=52083&r=mysqlcfg
